Synergistic compositions for the control of aerobacter aerogenes

ABSTRACT

The present invention relates to certain processes and compositions useful for inhibiting and/or controlling the growth of slime in water and, in particular, water employed for industrial purposes. Water employed in the manufacture of pulp paper and water employed in cooling water systems, as well as other industrial waters, provide environments which are conducive to slime formation. The novel compositions of the present invention are mixtures which show unexpected synergistic activity against microorganisms, including bacteria, fungi and algae, which produce slime in aqueous systems. The slime, of course, is objectionable from an operational and/or an aesthetic point of view. Specifically, the invention is directed to and the use of compositions comprising a combination of 5-chloro-4-phenyl-1,2dithiole-3-one and phenolic compounds (or mixtures thereof). The inventive compositions inhibit the growth of slime in water, or more specifically, possess biocidal activity against bacteria, fungi and/or algae. The phenolic compounds contemplated for use in accordance with the present invention are those phenolic compounds which possess the capacity to kill or inhibit the growth of slime-forming microorganisms such as bacteria, fungi and algae. The type phenolic compounds encompassed by the present invention may be exemplified by: phenol, ortho-phenylphenol, 2, 3, 4, 6-tetrachlorophenol, 4-chloro-2-cyclopentylphenol and 2chloro-4-phenylphenol.

United States Patent [191 Brink, Jr. et al.

[ Mar. 25, 1975 SYNERGllSTllC COMPOSITIONS FOR THE CONTROL OF AEROBACTER AEROGENES [75] Inventors: Robert H. Brink, Jr., Doylestown;

Bernard F. Shema, Glenside; Roger L. Justice, Cornwells Heights; Paul Swered, Philadelphia, all of Pa.

[73] Assignee: Betz Laboratories, Inc., Trevose, Pa.

[22] Filed: Apr. 4, 1974 [21] Appl. No; 457,743

Related US. Application Data [62] Division of Ser. No. 160,191, July 6, 1971, Pat. No.

[52] US. Cl 424/277, 71/67, 162/190, 424/346 [51] Int. Cl AOln 9/02 [58] Field of Search 7l/67; 424/277, 346, 347

[56] References Cited UNITED STATES PATENTS 2,997,380 8/1961 Josephs 71/66 3,031,372 4/1962 Brock 71/67 3,824,318 7/l974 Shema et al. 71/67 3,829,305 8/1974 Brink, Jr. 71/67 Primary E.raminer-James 0. Thomas, Jr. Attorney, Agent, or Firm.Alexander D. Ricci [57] ABSTRACT The present invention relates to certain processes and compositions useful for inhibiting and/or controlling the growth of slime in water and, in particular, water employed for industrial purposes. Water employed in the manufacture of pulp paper and water employed in cooling water systems, as well as other industrial waters, provide environments which are conducive to slime formation. The novel compositions of the present invention are mixtures which show unexpected synergistic activity against microorganisms, including bacteria, fungi and algae, which produce slime in aqueous systems. The slime, of course, is objectionable from an operational and/or an aesthetic point of view. Specifically, the invention is directed to and the use of compositions comprising a combination of 5- chloro-4-phenyl-l,2-dithiole3-one and phenolic compounds (or mixtures thereof). The inventive compositions inhibit the growth of slime in water, or more specifically, possess biocidal activity against bacteria, fungi and/or algae. The phenolic compounds contemplated for use in accordance with the present invention are those phenolic compounds which possess the capacity to kill or inhibit the growth of slime-forming microorganisms such as bacteria, fungi and algae. The type phenolic compounds encompassed by the present invention may be exemplified by: phenol, orthophenylphenol, 2, 3, 4, 6-tetrachlorophenol, 4-chloro- 2-cyclopentylphenol and 2-chloro-4-phenylphenol.

5 Claims, N0 Drawings SYNERGISTIC COMPOSITIONS FOR THE CONTROL OlF AEROBACTER AEROGENES This is a division of application Ser. No. 160,191, filed July 6, 1971, now U.S. Pat. No. 3,829,305.

BACKGROUND OF THE INVENTION an ideal environment for growth and multiplication.

Aerobic and heliotropic organisms flourish on the tower proper while other organisms colonize and grow in such areas as the tower sump and the piping and passages of the cooling system. Such .slime serves to deteriorate the tower structure in the case of wooden towers. In addition, the deposition of slime on metal surfaces promotes corrosion. Furthermore, slime carried through the cooling system plugs and fouls lines, valves, strainers, etc. and deposits on heat exchange surfaces. In the latter case, the impedance of heat transfer can greatly reduce the efficiency of the cooling system.

ln'pulp and paper mill systems, slime formed by microorganisms is also frequently and, in fact, commonly encountered. Fouling or plugging by slime also occurs in the case of pulp and paper mill systems. Of greater significance, the slime becomes entrained in the paper produced to cause breakouts on the paper machines with consequent work stoppages and the loss of production time or unsightly blemishes in the final product; this, of course, results in rejects and wasted output. The previously discusssed problems have resulted in the extensive utilization of biocides in cooling water and pulp and paper mill systems. Materials which have enjoyed widespread use in such applications include chlorine, organo-mercurials, chlorinated phenols, organo-bromines, and various organo-sulfur compounds. All of these compounds are generally useful for this purpose but each is attended by a variety of impediments. For example, chlorination is limited both by its specific toxicity for slime-forming organisms at economic levels and by the ability of chlorine to react which results in the expenditure of the chlorine before its full biocidal function may be achieved. Other biocides are attended by high costs, odor problems and hazards in respect to storage, use or handling which limit their utility. To date, no one compound or type of compound has achieved a clearly established predominance in respect to the applications discussed. Likewise, lagoons, ponds, lakes and even pools, either used for pleasure purposes or used for industrial purposes for the disposal and storage of industrial wastes become, during the warm weather, besieged by slime due to microorganism growth and reproduction. In the case of the recreational areas, the problem of infection, odor, etc. is obvious. In the case of industrial storage or disposal of industrial materials, the microorganisms cause additional problems which must be eliminated prior to the materials use or the waste is treated for disposal.

It is the object of the present invention to provide compositions for controlling slime-forming microorganisms in aqueous systems, such as cooling water sys tems and pulp and paper mill systems, and for controlling slime formation or microorganism populations in aqueous bodies in general. Moreover, another object of the invention is the provision of methods for preserving materials and for controlling slime-forming microorganisms in any aqueous system which is conducive to the growth and reproduction of microorganisms and, in particular, cooling water and paper and pulp mill systems. These methods employ a combination of 5- chloro-4-phenyl-1,2-dithiole-3-one and a phenolic compound (or mixtures thereof). The phenolic compound must possess the property of being biocidally active against bacteria, fungi and/or algae, i.e. either kill or inhibit the growth of these microorganisms.

In the practice of the invention, the combination is added to the particular material to be preserved or to the system being treated, for example cooling water systems, paper and pulp mill systems, pools, ponds, lagoons, lakes, etc., in a quantity adequate to control the slime-forming microorganisms which are contained by, or which may become entrained in, the system which is treated. It has been found that such compositions and methods control the growth and occurrence of such mi- I croorganisms as may populate these particular systems.

GENERAL DESCRIPTION OF THE INVENTION As earlier stated, the inventive compositions comprise a combination of 5-chloro-4-phenyl-1,2-dithiole- 3-one and a particular phenolic compound (or mix tures thereof) with either compound being present in such a quantity as to impart a synergistic behavior for the purpose to the composition as a whole, Preferably, the compositions contain a percentage by weight ranging from about 5 to about of the dithiole-3-one compound and from about 5 to about 95% of the phenolic compound. When these two ingredients are mixed either beforehand or by addition to the aqueous system individually, the resulting mixtures possess a high degree of slimicidal activity which could not have been predicted beforehand from the known activity of the individual ingredients comprising the mixture. Accordingly, it is therefore possible to produce a more effective slime-control agent than has previously been available. Because of the enhanced activity of the mix ture, the total quantity of biocide required for an effective treatment may be reduced. In addition, the high degree of biocidal effectiveness which is provided by each of the ingredients may be exploited without use of the higher concentrations of each. This feature is not only important and advantageous from an economical point of view, but also most desirable from the pollution or ecological standpoints. In this regard, it might be pointed out that the smaller the amount of a chemical that is required for effective treatment, the smaller the problem in treating the wastes from these systems. In both cooling water systems and in paper and pulp mill systems, certain discharge of waste water. e.g. blowdown in cooling water systems. is a necessity. However, because of the current concern and legislation regarding the discharge of wastes. the effluent waste water must be treated to reduce and, hopefully. to eliminate any undesirable constituents. This treatment, of course, is time consuming and costly. Accordingly, a reduction in additive usage will result in a corresponding reduction in costs for the treatment of wastes containing these additives.

To demonstrate the synergism which is obtainable from the combination of the phenolic compounds with the 5-chloro-4-phenyl-l,2-dithiole-3-one (supplied by Hercules Corporation under designation S-l6l2), various exemplary phenolic compounds were chosen. As earlier indicated, synergistic activity can be obtained by combining the dithiole-B-one compound with phenolic compounds which exhibit growth inhibitory or biocidal activity with respect to bacteria, fungi and/or algae. The phenolic compounds which were chosen as representative are as follows: phenol, orthophenylphenol (Dow Chemical Company Dowicide l); 2-chloro-4-phenylphenol (Dowicide 4); 2, 3, 4, 6 tetrachlorophenol (Dowicide 6); and 4-chloro-2- cyclopentylphenol.

In order to illustrate the synergistic activity, the efficacy and the comparative effectiveness of the compositions, various tests were utilized and will be described Microbiology, 9, 5384l, (1961)] and the relationships,

0.1/ QIl/Oh l is additivity I is antagonism l is synergism where,

For mixtures of compounds A and B, and for Compound A and Compound B acting alone, the following SYNERGISTIC COMBINATION:

Compound A: -chloro-4-phenyl-l,2-dithiole-3-0ne Compound B: Phenol The compositions of this Example contained 5- chloro-4-phenyl-l,2-dithiole-3-one (referred to as Compound A in the Test Equations and in Tables 1 through 1C) and phenol (referred to as Compound B in this Example and in the Test Equations and in Tables l through lC) in the weight ratios expressed in the Tables which follow. The compositions were tested for synergistic activity in accordance with the method described. The synergism test was utilized to evaluate each of the combinations of this Example and the following Examples.

Synergistic Index Test active ingredients working alone in concomitantly prepared culture bottles. Synergism was determined by the method described by Kull et al [F. C. Kull, P. C. Eisrnan, H. D. Sylwestrowicz and R. L. Mayer, Applied following. 7 results were observed:

TABLE 1 Weight Ratio Quantities Producing End Points (ppm) Q /Q of A to B .4 on Qi/Qa il h n Qn ture 100/0 4 (0..) 95/5 10.45 0.55 l .0 0.747 0.0003 0.75 /50 l0.0 [0.0 20.0 0.7 l 4 0.005 0.72 5/95 9.0 I7] 180 0643 0.086 0.73 OH 00 200 (Qh) SIECIFIC EMBODIMENTS It is evident from the data recorded in Table 1 that EXAMPLE 1 35 compositions of the present invention function to control slime growth due to microorganisms not only at equal portions of the respective ingredients, but also where just minor amounts of one or the other are present. This discovery of synergism at the lower levels is extremely valuable since it illustrates conclusively that the ingredients are compatible over the wide percentage by weight range.

BACTERICIDAL EFFECTIVENESS The bactericidaleffectiveness of the mixture of Compound A and Compound B of this Example is demonstrated by the following Table in which the inhibiting power of a 50/50 by weight mixture of A and B is shown. Aerobacter aerogenes was employed as the test organism and a substrate technique was utilized. Specifically, the biocidal mixture was added in gradually increasing quantities to nutrient agar media which was then inoculated with A. uerogenes. The preparation was then incubated for 48 hours. The values set forth in the Table indicate the quantity of biocide required, in parts by weight for each one million parts by weight of the medium, in order to achieve complete inhibition of the growth of the test organism.

TABLE lA Quantit (ppm) required for inhibition Biocidal Material of .4. acmt'unu Inert 5 FUNGICIDAL EFFECTIVENESS In order to test the effectiveness of the inventive mixtures in respect to fungi, evaluations were made following the procedures described by B. F. Shema and .l. H.

treated to serve as controls. The control portions are plated for total count at the beginning of biocide treatment and all portions are plated for total count at some suitable time period(s) after beginning biocide treat- Conkey [Journal for The Technical Association of The Usmg counts f f from the platmg the Pulp and Paper Industry 36 20A 3OA (1953)]. The percentage kill (based on the initial control count) may described procedure generally entails incorporating the be calculated evaluano the Sample "9 biocide under test in a nutrient substrate such as agar, taken from water of a paper machme located m malt, etc. and pouring the resulting medium into a Petri l fl ll fibsliesrno.o- ..o dish and allowing the medium to solidify. A button of For the purposes of comparison. the mixture of A fungus inoculum is placed on the surface of the solidiand B was evaluated together with two recognized fied medium and the medium is incubated for a period commercial biocides, Pentachlorophenol and a Comof 14 days. After the period, the diameter of the colony mercial Product. TABLE 1C Quantity of Percent kill Biocidal Material biocide (ppm) after 6 hours Compound A Compound B (5%), lnert (90%) 5 77 do. 89 do. 94 do. 50 99 do. 100 I00 Pentachlorophcnol( 10071) 5 82 do. 10 9l do. 25 100 do. 50 100 do. lOO lOO Commercial Product active: Combination of dithiocarbamates) 5 72 do. 10 72 do. 25 73 do. 50 78 do. 100 88 TABLE 18 Quantity (ppm) for inhibition Biocidal Material P. expunsum A. niger i Compound A(5%), Compound B(5%), 1

100 Inert (90%) sulviE CONTROL EFFECTIVENESS The inventive methods and compositions were alsol tested with respect to their performance in the controll of slime formation in industrial systems. In this test an industrial recirculating water was obtained from a sys-* tem which was currently experiencing problems in re-; spect to the formation of slime by microorganisms. Such tests do not demonstrate the efficiency of the bio-' cide employed with respect to specific species of microorganisms but instead supply a practical demonstra-l tion of the efficacy of the biocide tested, in relation to' those communities of microorganisms which have evidenced their ability to form slime in actual industrial systems.

in the testing of recirculating water samples, a substrate evaluation was employed. In such testing identical portions of water samples are treated with varying cen rat ns f Dism ss and we P r i s a l ft 9 1:

A perusal of the recorded percentages clearly establishes that the composition of the present invention, although less concentrated with respect to active ingredients as compared to the two commercial products, gave excellent rates of kill even at low treatment levels. As earlier expressed, excellent performance of a biocidal composition at low treatment levels not only provides a most desirable cost performance index, but also provides most desirable advantages from the aspects of pollution abatement, waste treatment costs and the preservation of the ecological strain.

Compound A: 5-chloro-4-phenyl-l,2-dithiole-3-on Compound B: Ortho-phenylphenol The compositions of this Example contained 5- 'chloro-4-phenyl-1,2-dithiole-3-one (referred to as Compound A in the Test Equations and in Tables 2 through 2C) and ortho-phenylphenol (referred to as Compound B in this Example). The compositions of this Example were tested in accordance with the test procedures outlined in Example I. The data ascertained for the respective tests are recorded below under the commensurate Table.

Synergistic lndex Test For mixtures of Compounds A and B. and for Compound A and Compound B acting alone. the following results were obseryed:

TABLE 2 Quantities Wei ht Ratio Producing End Pointsrslpprn) Q /Q of A to B A 0,, \xture Q /Q Qu/Qb 5/01,

I/0 l 1.0 95/5 9.5 0.5 10.0 0.864 0.004 0.87 50/50 6.0 6.0 l2.0 0.546 0.048 0.59 /95 3.0 57.0 .0 0.273 0.456 0.73 0/l00 I The above evaluation established that the compositions in the weight ratios evaluated all exhibited synergistic activlty. As set forth in the explanation of the test earlier in this text. when QA/Qn O /Q is less than 1, then the two individual components are acting in a synergistic manner.

BACTERICIDAL EFFECTIVENESS The bactericidal effectiveness of the combination of 20 this Example was tested in accordance with the procedure outlined in Example I. The values obtained are The composition was quite effective in controlling fungus growth when it is considered that it contained only 10% active material.

SLIME CONTROL EFFECTIVENESS The test procedure used was that explained in Example I. For comparative purposes. two commercial products were tested together with the composition of this Example. The water sample in this test was taken from the air-washer sump of an industrial plant located iqths1n r ea srp. l ts ta ss.

recorded in Table 2A which follows:

TABLE 2A Quantity (ppm) required for inhibition Biocidal Material of A. uurogmws Compound A (5%), Compound 8 (5%). 300

Inert (90%) The above data established that the combination'effectively inhibited the growth of the particular bacterial strain.

FUNGICIDAL EFFECTIVENESS The effectiveness of the composition of Example 2( was tested in accordance with the procedures set forth in Example 1. The results were:

TABLE 23 Quantity (ppm) for inhibition P. expunsum A. niger Biocidal Material Compound A (5%), Compound B (5%). 500 500 Inert The results obtained for the inventive composition were comparable to the pentachlorophenol at high treatment dosage and were overall superior to the Commercial Product which has found widespread acceptance and use. Moreover, when the low concentrations of the active ingredients are considered, it is obvious that the inventive composition was quite active in kill percentage.

EXAMPLE 3 SYNERGISTIC COMBINATION:

Compound A: 5-chloro-4-phenyll .2-dithiole-3-one Compound B: 2-chIoro-4-phenylphenol The combinations of this Example contained 5- chloro-4-phenyl l ,2-dithiole-3-one (hereafter referred to as Compound A) and 2-chloro-4-phenylphen0l (referred to in this Example as Compound B). As with the previous Examples, combinations of these ingredients were tested in accordance with the various test procedures outlined in Example I. The data obtained is recorded in the following Tables 3 through 3C.

Synergistic Index Test For mixtures of Compounds A and B. and for (ompound A and Compound B acting alone. the following results were observed:

TABLE 3 Quantities Weight Ratio Producing End Pointshglppm) Qi/Q" of A to B Q 0,, ixture Q /Q" QB/Qh Oil/Q!) The results obtained for this particular combination established unequivocally that the two ingredients behave synergistically together.

Again, the slime control effectiveness of the instant composition even at only three hour contact times was superior to the commercial products at low treatment ranges and was significantly better overall as compared BACTERICIDAL EFFECTIVENESS to the 30% active Commercial Product.

The test procedure as described in Example 1 was EXAMPLE 4 utilized. The results established that the composition SYNERGISTIC COMBINATION; was effective m controlling this strain of bacteria. Compound 5 Chl0ro 4 pheny| ],zdithiolesonfi Compound B: 2,3,4,6-tetrachlorophenol FUNGIClDAL EFFECTIVENESS Synergistic Index Test The fungicidal activity of the composition of this Example was tested in accordance with the procedure The synerglsnc f l of the Combmatlons of previously described. The results were; chloro-4-phenyl-1,2-d1th1ole-3-one (referred to as TABLE 33 Quantity (ppm) for inhibition Compound A) and 2,3,4,6-tetrachlorophenol (referred to in this Example as Compound B) was evaluated in accordance with the test described. The results were as follows:

Biocidal Material P. expansum A. niger For mixtures of Compounds A and B, and for Comt ;g% 2 1 B (5%), 500 500 pound A and Compound B acting alone, the following .5. s a t ..xvsxeebser TABLE 4 Weight Ratio Quantities Producing End Points (ppm) 0 /0,. of A to B Q, Mixture Q ,|/Q,, Q,,/Q,, OHIO),

Trial (11 100/0 18.0

/50 14.0 14.0 28.0 0.778 0.047 0.83 5/95 4.0 76.0 80.0 0.222 0.253 0.47 0/100 300 Trial (2) 100/0 5.0

SLIME CONTROL EFFECTIVENESS The combinations exhibited a 0.4/0 Q,,/Q,, of less The Slime Comm] ff ti f the present 45 than 1 which, ofcourse. established that the individual position was evaluated using actual paper mill water as explained under the procedure outlined in Example 1. As with the previous Examples, the composition was compared with commercially available products using -samples of water derived from the sump of an air- 0' washer of an industrial cooling water system located in the northeastern United States.

ingredients operated in concert to produce a synergistic result.

BACTERlClDAL EFFECTIVENESS The efficacy of the compositions of this Example was tested in accordance with the procedure outlined ear- H lier The resuitgof thetest clearly established that the TABLE 3C Quantity of Percent kill Biocidal Material biocide (ppm) after 3 hours Compound A (5%), Compound B (5%), inert 5 5 do. 10 63 do. 25 76 Edoudo. I00 Pentachlorophenol (100%) 5 4 do. 10 24 do. 25 71 50 98 do. 100 100 Commercial Product (30% active See Table IC) 5 0 do. 10 0 do. 25 5 do. 50 19 do.

, l 1 7 r it 7 g V 12 combination of the instant invention is effective even compositions were capable of controlling the slimeat low percentages of active ingredients. 7 forming organisms.

TABLE 4A EXAMPLE 5 Quantity (portray l l t Biocidal Material f i fiemgt n r 1 Ion SYNERGISTIC COMBINATION" Compound A (5%). Compound B (5%). 300 Compound A: 5-chloro-4-phenyll ,2-dithi0le3-one Inert (90%) Compound B: 4-chloro-2-cyclopentylphenol FUNGlClDAL EFFECTIVENESS syncrg'sm Index The fungicidal activity of the composition of this Ex- I ample was tested in accordance with the procedure ChIGm'4'PhCnyI'lz'dlthloles'one (referred to previously described. The result of this evaluation was' 15 compomld l and 4Chlom'z'cyclopemylphenoI I ferred to in this Example as Compound B) was evalu- The synergistic activity of the combinations of 5- as follows:

ated in accordance with the test described. The results TABLE 4B were as follows: W h Quantity (ppm) for inhibition BIOCIddl Material P. mpum'um A. Inger For mixtures of Compounds A and and for Compound A (5%). Compound B (5% 100 500 pound A and Compound B acting alone, the following Inert (90%) results were observed.

TABLE 5 Weight Ratio Quantities Producing End Points (ppm) I Q /Q. of A to B Q, Q MIXIUIL 0 /0 Qn/Qn QIl/Qh SLIME CONTROL EFFECTIVENESS All of the combinations tested exhibited a QA/Qu Qn/QI, of less than 1 which. of course; established that As in the previous Examples and in the manner set the individual Ingredients operated in concert to proforth in the previous Examples, the slime control effectiveness of the composition of the Example was tested. duce a synerglsuc result The outcome of this evaluation and the data derived using the Commercial Products are set forth in the fol- 40 lowing Table. The water sample. used in this test was BACTERICIDAL EFFECTIVENESS obtained from the airwasher sump of a cooling tower located in the northeastern United States. The efficacy of the compositions of this Example was TABLE 4C Quantity of Percent kill Biocidal Material biocide (ppm) after 6 hours Compound A (5%). Compound B (5%), lnert (90%) 5 35 do. 10. 45 do 25 64 do do. 100 Pentachlorophenol (l00%) 5 41 do. 10 59 do. 25 87 do. 50 100 do. 100 x00 Commercial Product (30% active See Table IC) 5 0 do. 10 0 do. 25 0 do. 5O 18 do. 100 28 The composition of this Example, as with the previtested in accordance with the procedure outlined car ous Examples, exhibited overall desirable and attrac- 65 lier. The results of the test clearly established that the tive slime control capacity. Of special interest is the combination of the instant invention is effective ewn fact that at low percentage active concentrations the at low percentages of active ingredients.

TABLE A Quantity (ppm) required for inhibition Biocidal Material of A. aerogenes 5 like, may be employed to enhance the dispersibility and Compound A (5 Compound B 300 stability ofthese dispersions. The foregoing solutions of lnert (90%) the biocidal compositions are utilized in order to insure the rapid and uniform dispersibility of the biocides within the industrial water which is treated. It has been FUNGICIDAL EFFECTIVENESS found that either aqueous or non-aqueous solvents are generally suitable in the preparation of compositions of s i i S gz ziggigg azgf f i i i" the invention, e.g., methyl cellosolve, organic solvents amp}? es Th 1* of i e a: such as the aliphatic and aromatic hydrocarbons, e.g. prefvlfius escn e e resu 1 on kerosene. Based upon the synergism study as outlined as 0 15 above, it was ascertained that in the treatment ofpaper.

TABLE 55 mill and cooling water, effective biocidal action is obtained when the concentration or treatment level of the Quantity (ppm) f inhibition combination or admixture of biocides is between 0.5 Biocidal M terial P. et/min'um A. Niger parts per million to 1000 parts per million, and preferacompound A (5%) Compound 8 (5%) 500 500 bly between 1 and 100 parts per million, based upon m (90%) the total content of the aqueous system treated, such as the total quantity of cooling water or paper mill water.

The compositions may also be utilized for the preser- SLIME CONTROL EFFECTIVENESS vation of slurries and emulsions containing carbohydrates, proteins, fats, oils, etc.; dosage levels for this As in the previous Examples and in the manner set purpose range in the vicinity of 0.01 to 5%. The comforth in the previous Examples, the slime control effecpositions of the invention which can be prepared by tiveness of the composition of the Example was tested. merely combining the respective ingredients and mix- The outcome of this evaluation and the data derived i th o ghly at standard conditions may be fed conusing the commercial products are set forth in the foltinuou ly to the treated system, e g,, by means ofa melowing Table. The water sample used in this test was tered pump, or may be fed periodically at predeterobtained from the water tray of a paper machine of a mined intervals calculated to control the growth of mill located in thenortheasternUnited States. slim e forming organisms in the system, Naturally, in

TABLE 5C Quantity of Percent kill Biocidal Material biocide (ppm) after 3 hours Compound A (5%), Compound B (571), lncrt (90%) 5 38 do. i0 84 do. 25 86 do. 92 do. 100 95 Pentachlorophenol (100%) 5 89 do. 10 94 do. 25 100 do. 50 100 do. 100 I00 Commercial Product (30% active See Table 1C) 5 38 do. 10 36 do. 25 9 do. 50 0 do. 100 36 The composition of this Example exhibited overall 7 the treatment of cooling water, the feeding of the indesirable and attractive slime control capacity. Of speventive compositions must be designed to compensate cial interest is the fact that at low percentage .active for blowdown in those systems which employ that expeconcentrations the compositions were capable of condi ent. trolling the slime-forming organisms. 1

When the inventive compositions are employed in 9 the folegomg has f spFclficdlly 'l to liquid formulations. the combinations of the inventhe treatment of cooling or paper mill water, they are I V I tion may, of course, be formulated dry with ell-know n preferably utilized in the form of relatively dilute solu I y pelletizing agents, e.g. sodium chloride, talc, alummate. tions or dispersions. For example, a preferred solution 0 etc. to produce solid pellets or briquettes which are comprises between 5 to /b by weight of the synergisy added directly to the systems to be treated. The pellets tic combination in admixture with various solvents and r h )lubilmny agents An example of Such a Synergistic or briquettes. of course. dissohe in accordance ll 65 predetermined conditions or rates.

biociclal product comprises from about 5 to 10% by weight of the phenol, from about 5 to 10% by weight of the 5-chloro-4-phenyl-l,2-dithiole3-one and the re mainder composed of such materials as surfactants, staln describing the inventive subject matter. the expression composition" has been utilized. However. it is to be understood that physical compositions or combinations are not the sole utility of the invention. If, for example, the separate ingredients of the composition" are added independently to a particular system, it is intended that this usage of the subject matter is within the scope of the invention and is to be construed within the broad interpretation of composition" and/or combination.

As would be expected, the inventive composition may be added to the cooling water or paper and pulp mill systems at any convenient point. Naturally, in once-through or non-circulating systems, the composition must be added upstream from the point or points at which microorganism control is desired. In circulating systems or pulp and paper systems, the compositions must be added at any point provided that the time lapse and the conditions experienced between point of addition and the point at which the effect of the composition is to be experienced are not so drastic as to result in the neutralization of the effect of the composition.

Although the invention has been described specifi cally as being directed to specific compositions comprising -chloro-4-phenyl-1,2-dithiole-3-one in combination with the phenol as described in Example 1, the phenylphenol of Example 2, the 2-chlorophenylphenol of Example 3, the chlorophenol of Example 4 or the pentylphenol of Example 5, it is obvious that homologues, analogues, etc. of the dithiole-3-one compound certainly are operable for the purpose. Likewise, the derivatives of the specially exemplified organobromine compounds also have utility in the present inventive concept. Moreover, as earlier described, mixtures of the various organo-bromine compounds would also serve the purpose. The provision, of course, is that the organo-bromine compound possesses biocidal or growth inhibitory capacity with respect to bacteria,

16 fungi, and algae.

It should be noted that the evidence has been derived from the treatment of samples taken from paper and pulp mill aqueous systems, the compositions and methods of the present invention are broadly applicable to the treatment of aesthetic water as well as industrial waters such as cooling waters which are plagued by dcposits formed by slime-forming organisms, 0r by the very presence of such organisms.

Having thus described the invention, what we claim l. A method for controlling the growth of the microorganism Aerobacter Aerogenes in an aqueous system in which said microorganism is found which comprises adding to said system so as to contact said microorganism an effective amount of a combination comprising 5-chloro-4 -phenyl-one.2-dithiole-3-l and 2-chloro-4- phenylphenol, wherein the weight ratio of the dithiole to the phenylphenol is from 5 to to 95 to 5%.

2. The method of claim 1 where said weight ratio is 50 to 50%.

3. The method of claim 1 where said combination is added to said system in an amount of from 0.5 to about 1000 parts by weight of said combination per million parts by weight of said aqueous system.

4. A composition which is effective in controlling the growth of the microorganism Aerobacter Aerogenes in aqueous system where said microorganism' is found which comprises 5-chloro'4-phenyl-one,2-dithiole-3-l and 2-chloro-4-phenylphenol, wherein the weight ratio of the dithiole to the phenylphenol is from 5% to 95% to 95% to 5%.

5. The composition of claim 4 wherein said weight ratio is 50% to 50%.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No- 73, 710 Dated March 25, 1975 I Robert H. Brink, Jr. et a1 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Delete 1 and substitute one therefor in the patent as follows:

Column 16, line 17; line 29.

Signed and sealed this 20th day of May 1975.

(SEAL) Attest C. MARSHALL DANN RUTH C. MASON Commissioner of Patents Attesting Officer and Trademarks FORM Po-1050 (10-69) USCOMM-DC 60376-P69 U.S. GOVERNMENT PRINTING OFFICE 199 0-366-335 

1. A METHOD FOR CONTROLLING THE GROWTH OF THE MICROORGANISM AEROBACTER AEROGENES IN AN AQUEOUS SYSTEM IN WHICH SAID MICROORGANISM IS FOUND WHICH COMPRISES ADDING THE SAID SYSTEM SO AS TO CONTACT SAID MICROORGANIXM AN EFFECTIVE AMOUNT OF A COMBINATION COMPRISING 5-CHLORO-4 -PHENYL-ONE.2DITHIOLE-3-1 AND 2-CHLORO-4-PHENYLPHENOL, WHEREIN THE WEIGHT RATIO OF THE DITHIOLE TO THE PHENYLPHENOL IS FROM 5 TO 95% TO 95 TO 5%.
 2. The method of claim 1 where said weight ratio is 50 to 50%.
 3. The method of claim 1 where said combination is added to said system in an amount of from 0.5 to about 1000 parts by weight of said combination per million parts by weight of said aqueous system.
 4. A composition which is effective in controlling the growth of the microorganism Aerobacter Aerogenes in aqueous system where said microorganism is found which comprises 5-chloro-4-phenyl-one,2-dithiole-3-1 and 2-chloro-4-phenylphenol, wherein the weight ratio of the dithiole to the phenylphenol is from 5% to 95% to 95% to 5%.
 5. The composition of claim 4 wherein said weight ratio is 50% to 50%. 